Wire feed for magnetic recorders



April19,1949." v l. A. STONE 2,467,507

WIRE FEED FOR MAGNETIC RECORDERS I Filed July s, 1946 9 Sheets-Sheet 1 INVENTOR'.

IPA 115 )7. JZarre.

April 19, 1949. l. A. STONE WIRE FEED FOR MAGNETIC RECORDERS 9 Sheets-Sheet 2 Filed July 5, 1946 ILA. STONE WIRE FEED FOR MAGNETIC RECORDERS A ri: 19, 1949.

9 Sheets-Sheet 5 Filed July 3, 1946 I. A. STONE WIRE FEED FOR MAGNETIC RECORDERS April 19, 1949.

9 sheets-sheet 4 Filed July s, 1946 INVENTOR. r a 2, /7, Ji /(e.

' H T Tfi/YEVE'.

April 19, 1949. 1. A. STONE WIRE FEED FOR MAGNETIC 'RECORDERS 9 Sheets-Sheet 5 Filed July 3, 1946 I- A. STONE WIRE FEED FOR MAGNETIC RECORDERS April 19, 1949.

9 Sheets-Sheet 6 Filed July 5, 1946 I. A. STONE WIRE FEED FOR MAGNETIC RECORDERS April 19, 1949.

9 Sheets-Sheet 7 Filed July s, 1946.

INVENTOR.

fJ Z/ g /7 April 19, 1949.

Filed July 5, 1946 l. A. STONE 2,467,507

WIRE FEED FOR MAGNETIC RECORDERS 9 Sheets-Sheet 8 M3 INVENTOR.

A ril 19, 1949. A. STONE 6 WIRE FEED FOR MAGNETIC RECORDERS.

Filed Juiy s, 1946 9 Sheets-Sheet 9 I I I 59 INVENTOR.

EJJJ. firing 4526/74?) VZLLQ" Patented Apr. 19, 1949 UNITED STATES Irving A. Stone, Detroit, Mich., assignor to Wirecorder Corporation, Detroit, Mich, a corporation of Michigan Application July 3, 1946, Serial No. 681,213

4 Claims.

The present invention relates to magnetic wire sound recording and reproducing apparatus.

In apparatus for this purpose, it is customary to feed the wire from a wire spool to a take-up spool during recording or play back and thereafter rewind the wire on the wire spool. In the past it has been the practice to employ a small wire spool for convenience in manufacture and to facilitate storage of recordings, and a large diameter take-up spool which is driven at constant speed. With this arrangement the take-up spool must be much larger in diameter than the wire spool; otherwise the speed of the wire will vary to an objectionable extent as the thickness of the wire layer on the spool builds up. Due to the difliculty of handling the individual spools of very fine wire and of threading the wire by hand into the recording head, it has been proposed that both spools be enclosed in a removable magazine so that no handling of the separate spools or of the wire is required. This necessitates the use of a small take-up spool in order to reduce the size and cost of the magazine, and the small take-up spool, in turn, requires the use of special means to insure a constant wire speed. The copending application of Mortimer A. Neff, Serial No. 608,531, filed August 3, 1945, is directed to a machine adapted for use with a magazine, and the present invention constitutes an improvement over the machine of that application, although a number of the features of the present invention may be employed to advantage without amagazine.

It is the general object of the invention to provide a magnetic wire sound recording and reproducing apparatus of novel and improved design construction and mode of operation.

Another object of the present invention is to provide an improved wire feeding means of the type which grips the wire at a point between the spools and which includes means for exerting considerable pressure on the wire without requiring exertion of any appreciable manual efiort to either grip or release the wire.

Another object of the present invention is to provide improved manually or automatically operable means for stopping the apparatus.

Still further, the present invention contemplates means to lock the control mechanism in either of two operating positions and further means responsive to a predetermined unwinding of the wire on the spools of either spindle for releasing this locking means and thereby'stoping the machine.

Further objects and advantages of the present invention will be apparent from the description which follows when considered in connection with the accompanying drawings, in which like numerals indicate like parts wherever shown, and wherein:

Figure l is a plan view of the chassis with a wire spool and a take-up spool in assembled relation and with the top casing removed, illustrating certain of the apparatus interiorly of said chassis;

Figure 2 is a plan view of the upper portion of the apparatus with the casing broken away and illustrating the driving mechanism of the present invention; Figure 3 is an elevational view taken on line 33 of Figure 2, illustrating the mechanism of the machine of the present invention, with the parts in the play position;

Figure 4 is an elevational View similar to Figure 8 and illustrating the mechanism of the machine of the present invention in an intermediate position prior to being brought into play position;

Fig. 5 is an elevational view similar to Figure 3 and illustrating the various parts thereof in position to rewind the wire;

Figure 6 is an elevational view taken in the direotion of arrow 6 on Figure 2 and illustrating the means for driving the level-winding mechanism on the left-hand side of the apparatus;

Figure 7 is a sectional elevation taken on line l-l of Figure 2 with certain of the parts broken away;

Figure 8 is a sectional elevation taken on line 8-3 of Figure 1 and illustrating the release plate;

Figure 9 is a sectional elevation taken on line 9 of Figure 1 showing the cam operated switch for the motor;

Figure 10 is a sectional elevation taken on line Il?-!il of Figure 1 illustrating the brake for the take-up spool;

Figure 11 is a section taken on line H-H of Figure 1 showing the control rod;

Figure 12 is a section taken on the line l2l2 of Figure 6 to illustrate the construction of one of the eddy current clutches;

Figure 13 is a partially sectioned elevational view of one of the spools, with the wire substantially unwound therefrom to illustrate the automatic stop operation;

Figure 14 is a section taken on line 3-44 of Figure '5; and

Figure 15 is a section on line l5-l5 of Figure 1 showing the pad for supporting the feed roll yoke positioned against the cam arm.

The apparatus of the present invention includes a base I, in the form of a casting, which is enclosed within a housing or cover 2, which cover is only partly shown in Figure 2, being broken away in order that the mechanism of the present apparatus might be more clearly seen.

This base portion I, as well as the housing 2, may be made of any suitable construction and it will be understood that the electrical circuits and elements of the magnetic apparatus may be enclosed within the same housing, if desired. Since these electrical circuits form no part of the present invention, they are neither illustrated nor described herein, but it will be understood that they are of any desired or conventional construction.

A wire spool 3 and a take-up spool 4 may be mounted upon spindles 5 and 6, respectively, and if a magazine is to be used for such spools, cover 2 is designed to receive the same in any desired manner, such as that shown in the aforementioned Neif application.

To drive wire spool 3 and take-up spool 4, a constant speed electric motor 'I is mounted by means of suitable supports provided therefor in the base I. Means are provided for selectively driving either or both of the spindles 5 and 6 for said wire spool and take-up spool respectively. from said motor I through magnetic clutches of the eddy current type, which will permit continuous slipping in the drive connection between the spindles and the motor. Thus, as best shown in Figures 2 and 6, the spindle 6 is journaled for rotation in bearings 8, 9 and I carried by a pillow block II which is pivotally secured to the base I. by a vertical pivot pin I2, positioned near the forward face of the housing 2 and secured in place by means of nut I3 and lock nut I3a. The rearward end of spindle 6 carries a cuplike member I4, which is of nonmagnetic metal but which is a good conductor of electricity and, as shown in Figure 12, surrounds the multipole magnet rotor I5 and fits within an iron or soft steel housing I6. The housing I6 and the permanent, multipole magnet I 5 are fixed to a sleeve or bushing IT. This bushing I1 is rotatably supported by spindle 6 and provides for independent rotation of housing I6 and magnet I5 about such shaft. The elements I4, I5 and I6 constitute an eddy current clutch, with the result that, on rotation of the housing I 6, a rotary torque will be transmitted to the cup I4 and, consequently, to the spindle 6 for driving the take-up spool 4. The shaft of motor I is provided at the rear with a drive roller I8 having a circumferential rubber rim I9 adapted to frictionally engage and rotate the housing I6, and, as stated in the foregoing. causes a rotary torque to be transmitted to the cup I4 and thus drives the spindle 6 and take-up spool 4.

In a similar manner, spindle 5 is supported upon a pivoted pillow block 20 which is identical in construction and mode of operation to the previously described pillow block II, and this spindle 5 is likewise connected to the drive roller I8 by means of the housing of a magnetic, eddycurrent clutch 2|, identical to the previously described magnetic clutch I4I6. The rearward end of pillow blocks II and 20 is held by means of contractible springs 22 and 23, respectively, in such position as to normally hold the housings of magnetic clutch I4--I6 and magnetic clutch 2| in engagement with the member I9 on roller I8 at the same time, with the result that spindles 6 and 5 are subject to a winding torque in a counterclockwise direction when motor I is running and the remaining parts are in the stop position. As will hereinafter become more clear, the wire is so wound on wire spool 3 and take-up spool 4 that the winding torque thus applied to spindles 5 and 6 tends to wind the wire on both spools simultaneously and, consequently, substantially balance each other. As a result, when the parts are in the stop position and the motor is started, the slack wire between the spools is taken up with substantially no movement of either spool.

As a means for selectively controlling the operation of the apparatus of the present invention, a rotatable control knob 24 is provided. Such knob 24 is fixed to control shaft 25 which is journaled at its forward end within bearing 26, of the support 21 provided on the forward wall of casing I, and has the opposite end in bearing 28 in base I, as may be seen in Figure 1. This control knob may be rotated through substantially and provides for selectively placing the apparatus of the present invention in operation or stopping the same. Connected to the control knob is a main cam, indicated generally at 23, and having cam surfaces 30, 3I and 32. When the control knob 24 is in its stop or off position, the main control cam will be in such position that the cam surface 30 depresses a button 33 of switch 34 which controls the supply of current to motor I. When the button is depressed, the switch is opened. At the same time, the surface of cam 3I is free from a pad 35 on the bell crank shaped lever 36, shown best in Fig. 10, which is pivoted at 31 to base I, permitting the brake surface 33 on such lever 36 to be forcibly held by means of spring 39 against the outer diameter of cup I4. It will be apparent that upon initially moving control knob 24 in either direction from the stop position, cam 33 will disengage the button 33, while cam 3| will enter into engagement with pad 35 of lever 36. When this occurs, switch 34 closes the motor circuit, thereby starting the motor and releasing cup I4.

As shown in Figure 1, a rod 40 is threaded into the web portion of pillow block I I and positioned in such manner that the rounded end thereof may contact cam 32, in which position rod 40 is locked by means of a lock nut 4I abutting the web of the pillow block. This rod 40 is adapted to be shifted within the slotted openings provided at 42 and 43 in the base I. In like manner, a rod 44 is threaded into the web of pillow block 20 and locked in positio by means of lock nut 45 in such a manner that its rounded end may enter into engagement with cam 32. Rod 44 is also slidably mounted within slotted openings 46 and 41 provided in base I. When control knob 24 is in the stop or off position, cam 32 does not contact the rounded ends of either rod 40 or rod 44, and the member I9 of driving wheel I8 on motor I may contact the housings of both magnetic clutches for driving the same and causing the slack in the wire to be taken up, as previously described. However, after initial rotation of control knob 24 to start motor I and release brake 36, continued rotation of control knob 24 in either direction will cause cam 32 to come into contact with the rounded end of rod 40 or 44, depending upon the direction of rotation of such control knob, and thereby effect pivotal shifting of one of the pillow blocks. This causes disengagement of one or the other of the housings from the frictional drive roller I8. Cam 32 is so positioned upon main control cam 29 that when control knob 24 is rotated counterclockwise from a stop or ofi position to rewind position, the final portion of ment of cam 32 with the rounded end of rod 40 serving to move pillow block H pivotally about pin l2, thereby disengaging the housing [6 from the motor driving wheel l8. Similarly, rotation of control knob 24 in a clockwise direction toward play or record position, efiects engagement of cam :22 with the rounded end of rod 44 causing pillow block 29 to shift pivotally for moving magnetic clutch 2! out of engagement with the driving means. However, in this case clutch 2| is disengaged in advance of completion of the movement of the knob to play or record position.

The means for engaging and driving the Wire when it is being wound upon the take-up spool 4 is shown in Figures 3, 4 and 5. This means comprises a roller 48 mounted'on the-forward end of the motor shaft and adapted to be brought into engagement with a capstan drive roller 49. This roller 49 is rotatably supported by a shaft iii? journaled for rotation in the bearings 5i and 52 of a yoke 53 which is pivotally mounted by means of a pin 5% on an upwardly projecting lug 55 provided on base I. The shaft 50 projects forwardly through the bearings provided on yoke 53, as best shown in Figure 2, and carries a nonferrous metallic capstan wire drive roller 56.

The capstan drive roller 49 is only in engagement with roller 45, on the forward end of motor "I, when the control knob is rotated to play position, and this engagement is brought about at the end of the rotation of the control knob in such direction. In order to effect such engagemerit, a lever 57 is secured to the lower end of yoke 53 and extends laterally substantially normal to such yoke. Yoke 53 is urged by a spring 5101, in a direction to force a pad 58 on the outer end of lever 5'! into engagement with an annular portion or" a sleeve 55. Sleeve 59 is also mounted upon control shaft 25 for rotation therewith by means of control knob 24. As may be seen in Figure 15, the sleeve 59 is provided at one point with a flat, and when control knob 24 is turned to play position, pad 58 is urged into contact with the fiat, thereby allowing capstan drive roller 49 to contact roller 48 and efiecting driving of the capstan drive roller and capstan roller 56.

In order to effect a driving engagement between the wire and the capstan roller 56 in play position, there is provided a rubber pinch roller 58 carried by pinch roller arm 5| also pivotally supported by pin 54. As will hereinafter become more clear, the wire is pinched between rollers 55 and 58 with considerable pressure to establish a driving connection between the wire and roller 55. When the control knob is in ofi position or in the rewind position, which latter position is illustrated in Figure 5, the roller 60 is out of engagement with roller 56. The arrangement is such that rotation of control knob 24 toward play position first efiects starting of motor 1 to start rotation of spindles 5 and. 6 and thereby initially tensioning the wire. In order that motor I may come up to speed as rapidly as possible, continued rotation of the control knob in this direction next efiects disengagement of magnetic clutch 2| by shifting pillow block 20 outwardly. This relieves motor 1 of the torque load imposed by such clutch. When clutch 2| is disengaged from drive roller 19, its housing engages brake 62, which is carried by a stationary bracket 63. Thereafter, on continued movement of the knob,

the pinch roller is swung into engagement with the capstan roller 55. Subsequent to such engagement, means operated by further movement orknob' 24 applies a pinching pressure to the pinch roll. By the time all of these functions have been performed the motor is up to speed and substantial torque is being applied to the take-up spool. The capstan drive roller is then engaged with roller 48 by the final movement of knob 24. The mechanism for operating the pinch roller includes a pair of arms 65 and 6B fixed to the previously mentioned sleeve 59, which is pinned at 64 to shaft 25. The arms 65 and 66 rotatably support a roller 6! which, on rotation of sleeve 59, contacts the lower curved edge 69 on pinch roller arm 6|, serving to rotate such arm about pivot pin 54 in a counterclockwise and upward direction. This elevates roller 60 and therefore the wire Ill until, when the parts are in the position of Figure 4, the wire is engaged between rollers 56 and 6D.

Thereafter, continued rotation in this direction operates the pressure applying means which forces roller 60 against roller 56 with a heavy pressure. This means includes an arm 12 having a slot H formed at one end. The arm 12 is pivotally mounted by means of a slot 13 in its upper end which fits over a pin 14 on an car 75 that projects rearwardly from the yoke 53. To retain arm 12 on pin M, a relatively stiff spring l6, which may be seen best in Figure 14, has one end thereof secured to pin 14 and the other end fixed to a clip H which is pinned to arm 12 by means of a roller 18, permitting the force exerted by said spring to maintain arm I2 in position on pin 14.

It will be observed that a portion of arm 12 lies against a projecting portion Bio of pinch roller arm SI, and that roller '18 i adapted to engage the curved edge E9 of this portion 6la.

When the parts are in the oif or rewind position, the roller 78 engages the left-hand extremity of edge 19, as shown in Fig, 5, in such a manner that the line of the force exerted on edge 19 by roller 18 passes slightly to the left of the center line of pin 54. Consequently, spring 16 exerts no force tending to elevate arm 6| and may exert a slight force tending to hold it down. As clearly shown in the drawings (Figs. 4 and 5), the upward movement of arm 6|, previously described, causes roller 78 to move along a portion of edge 79 which is arouate in form and concentric with pin 14. Accordingly, no change in the length of spring 16 occurs during such movement. As a result, spring 16 offers no resistance to rotation of knob 24.

Continued rotation of the control knob after the parts reach the position of Figure 4, causes roller 68 to enter slot H and move arm 12 in a counterclockwise direction albiout pin E4, thus continuing the movement of roller 18 outwardly along the remainder of the edge 19 on roller arm 6|. This remaining portion of edge '19 is concentric with pivot pin 14 when rollers 55 and 60 are engaged. Consequently, the length in spring 76 remains constant during the swinging movement of arm 12 as roller 13 travels along the curved edge 19. This increases the lever arm of the spring force acting on arm 6| and thereby increases the pinching force on wire '16. Inasmuch as the length of the spring l6 remains unchanged throughout this operation, it will be appreciated that at no time does the spring resist turning of the control knob 24.

During this rotation of control knob 24 and slightly after pin 63 enters slot H in arm '12, but in advance of the-time roller 18 reaches the outemnost end or the curved edge 79, roller 61, which was in engagement withthe lower'curved edge 89 on the pinch roller arm 8 I, moves into engagement with the curved lower edge 80 of an arm 8|. This arm 8| is also pivotally mounted on pin 54 and rotatably supports at its outer end a. glass roller 82. Normally, roller 82 is in a lowered position, as illustrated in Figure 5, due to the effect of the spring 83 which is secured to a lug 84 on arm 8I and to pin 85 positioned in base I. However, roller 61, now in engagement with edge 80 of arm 8|, causes such arm to move upwardly and counterclockwise, allowing roller 82 to bring wire 10 into a playing and recording head 89.

When the control knob reaches the limit of this clockwise rotation, it is automatically locked in that position bymeans of a latching mechanism. This mechanism comprises a latch plate 81 which is mounted by means of pins 88 and 89 on pivoted supported levers 90 and SI, respectively, at opposite extremities of such plate. The plate is normally in latched position and against a stop 92 at'the left end thereof by means of a spring 93 fixed between the left end of the plate and base I.

Within an opening 94 in the latch plate 81 there is provided a downwardly directed latching finger 95 having a retaining slot 99. Toward the end of the clockwise rotation of the control kndb, the lower surface of latch 95 is engaged by pin 91 carried in one extremity of the irregularly shaped arm 98 which is an integral part of the previously mentioned sleeve 59. This engagement causes the latch plate to move toward the right and spring 93 to expand. As soon as pin 91 clears the upper edge of the latch finger 95 which, as stated in the foregoing, occurs when the control knob reaches the limit of clockwise rotation, spring 93 contracts, returning the latch plate 81 toward the left, and locking pin 91 in slot 96, as illustrated in Figure 3.

Assuming the mechanism is locked in play position, the same may be manually unlocked for returning the control knob to off position at any instant regardless of whether or not the wire is completely unwound from wire spool 3. Means, to be later described, are provided for automatically unlocking and stopping the mechanism before all wire is completely unwound from either spool; however, at thi point only the manual stop is described.

This stop comprises a stop button 99 positioned to move slidably in an opening provided therefor in base I immediately below control knob 24. Stop button 99 is connected to a bell crank I which, in turn, is pivotally secured at IN to the bottom of post I02. This post I02 depends from the previously described bracket 21 and is of such length that the free end I03 of the bell crank may contact an inwardly directed tab I04 on latch plate 81. When stop button 99 is pressed inwardly, the free end I03 of the bell crank forcibly bears against tab I04, causing latch plate 81 to move toward the right sufficiently to free pin 91 from slot 96. At that time, a spring I05 returns the control knob 24 to off position.

This spring I05 extends between lug I06 on arm 98 and base I and is normally horizontal with respect to base I, tending to retain control knob 24 in off position or return it to that position. However, rotation of the control knob to play position causes this spring to elongate and, therefore, as soon as pin 91 is freed from slot 98 in latch 95, spring I05 returns control knob 24 to off position. When this occurs, of course, pinch roller 80 and glass roller 82 are lowered.

releasing and lowering wire 10, both eddy current clutches are engaged with the drive roller I8, the motor switch is opened and all operation of the mechanism ceases.

Thereafter, if it is desired to rewind the wire, control knob 24 is rotated counterclockwise. This starts motor 1 again and releases brake 38, allowing the magnetic clutches to initially tension the wire between the spools. Further rotation of the control knob permits cam 32 to contact rod 40 for shifting pillow block II to disengage clutch I4I6 from motor roller I8 and bringing the same into contact with an adjacent brake I01 on bracket I01a. Brake I01 is made of felt and is designed to slow take-up spool 4 only sufiiciently to prevent overrunning and throwing of a loop during rewind. In this operation, clutch 2| is substantially unopposed and, consequently, a rapid rewind results.

At the same time, this counterclockwise rotation of the control knob moves pin 91, on arm 98, into engagement with a latch finger I08 on latch plate 81. Such latch finger is spaced from latch finger and is so disposed as to extend into opening 94 and be contacted by pin 91 as the same is rotated in this direction. Continued rotation of the control knob in this manner serves to effect shifting of latch plate 81 toward the right until pin 91 clears latch finger I08. When this occurs, pin 91 is locked in retaining slot I09 by the action of spring 93 as the same returns latch plate toward the left.

After the rewinding operation is complete, the control knob is simply returned to off position by releasing the latch plate and all portions of the mechanism return to the off position.

Because of the relatively great speed of rotation of the take-up spool in this rewind operation, it is particularly desirable that a retardin force be applied to the drive connection at the spool side of the yielding clutch mechanism I4-I6 when the control knob is returned to off position. As the control knob returns to off position, clutch I4-I6 re-engages motor roller I8 and this imposes a counter rotative torque tending to stop rotation of spool 4, but such retarding is efiective at the driving side of the clutch. Due to the slippage between clutch elements I4-I6, there is a tendency, because of the speed of rotation of spool 4, to continue rotating. For this reason, additional braking is provided on the spool side of such clutch. The previously described brake 38 supplies this additional braking as it engages cup I4 and thus prevents throwing of a loop in the wire when the control knob is returned to off position by spring I05.

In order to insure that the playing or recording head 86 will make proper engagement with wire 10 during recording or the reproducing of sound without interfering with the necessary level winding of the wire on the take-up spool 4 and to avoid the use of a separate level winding mechanism, the playing or recording head, in accordance with the present invention, is itself mounted upon a level winding mechanism in the manner illustrated in Figures 2, 3, 4 and 5. As there shown, the pick-up head 86, which is of conventional construction, is fixed to a bar or a rod 0 which is inserted in an opening provided therefor in an annular portion II I of the bracket II2 anchored to the base. The annular portion III of bracket H2 is provided with a slot H3 in the top thereof and a pin I I4, carried by bar H0, is received in slot II3 for effecting sliding movementof bar IIO as pin I I4 is reciprocated. This reciprocation of bar II is effected by means of a double-ended lever H pivoted at H6 to the upper surface of bracket H3, to be pivotally moved about such pivot H6 in the following manner.

A supporting bracket H1 is anchored to the pillow block H in overlying relationship to spindle 6. Such bracket H1 rotatably supports a gear H8 and a heart-shaped cam H9 adapted to be rotated as the gear H8, which meshes the worm I20 provided on spindle 6, is caused to be rotated by such spindle. A plate I2I is held to bracket II1 on the side of such bracket adjacent one end of the double-ended lever H5 and slidably supports a slide bar I22. On the inner face of slide bar I22, pins I23 and I24 project outwardly therefrom to enter into engaging relationship with the surface of cam H9 and effect reciprocation of the slide bar I22 as gear H8 drives cam H9. At one end of the slide bar I22, a tab is turned outwardly therefrom and provides a pin I25 adapted to operatively engage the double-ended lever I I5. Thus, it will be observed that as reciprocation of slide bar I22 occurs, lever H5 will effect reciprocation of bar II 0 and head 86 therewith. As a result of this arrangement, the head 86, which has wire engaging means, will operate back and forth in a direction parallel to spindle 6 in timed relation with the speed of rotation of the spindle and will thus insure a level winding upon the take-up spool 4.

In rewind such level winding mechanism is-not effective because the'wire is not in the head. However, the wire being level wound on the takeup spool 4, automatically level Winds as it is rewound on wire spool 3.

When the spools are installed on the apparatus as illustrated in Figures 1, 6 and 7, the forward extremities of spindles 5 and 6 enter into driving engagement with the spools 3 and 4 respectively. To accomplish this, there is provided on the forward end of spindles 5 and 6 annular members I26 and I21 respectively, for effecting this driving engagement with the wire spool and take-up spool.

Inasmuch as each of these annular portions is identical, only one is described. As may be seen in Figure 6, member I21, which engages take-up spool 4, is provided with diametrically opposed keyways, as indicated at I28 and I29, adapted to receive a clip I30. This clip I30, which may be made of spring wire, is bent in the form of a U and provides short inwardly directed leg extremities I3I and I32 substantially normal to the longitudinal axis of such clip. The short legs I3I and I32 are stationed within openings provided therefor in annular member I21, and the bottom of the U frictionally engages the forward face I33 of the keyways formed in such member I21. This clip I30 provides, in two places, a V which is indicated at I34, and each extends outwardly in a direction opposite to the legs formed on such cup.

.To provide for mounting spool 4 on spindle 6, such spool has a hub I35 having an axial opening I36 centrally thereof. Opening I36, is sufficient in diameter to receive annular member I21 of spindle 6 and there is provided internally of hub I35 a plurality of longitudinally disposed keyways I31 which are blind at one end. The open ends of such keyways are closed by means of the inner web I38 of spool 4, which is centrally positioned on such spool, and has a central opening I39 of the same diameter as opening I36 in the spool hub. When spool 4 is brought into position on spindle 6, the circumferential edge of opening I39 in this web I33 engages the slanting side members of clip I20. As the spool is pushed onto the spindle, this engagement causes the web to press each V down, allowing the Web to pass over the same. Movement of the spool onto the spindle is then continued until the outer face of web I38 contacts shoulder I40 on member I21. At this time, web I38 has passed over each V on clip I30 and the same spring up into diametrically opposed keyways in the spool hub, securely locking the spool to the spindle.

It will be apparent that, if desired, the member I21 may be omitted and the shaft 6, itself, formed. to receive the clip I30. Also, the inward movement of the spool may be limited by engagement of the end of shaft 6 with the end plate of the spool.

It will be observed in Figure 5' that with the spools thus mounted on the spindles, the stretch of wire between the spools is located substantially below capstan roller 56 and head 06. Consequently, it is possible to install the spools without interference between the wire 10' and such members.

As described in the foregoing, the wire is raised from this lowered position by means of pinch roller 60 and glass roller 82 when the control knob is turned to play position. In this manner and without manual aid, it is possible to bring the wire into engagement with capstan roller 50 and into a guide I4-I on head 86 which directs the wire into thegroove provided therefor in such head.

The wire spool and the take-up spool each provides means for automatically stopping the apparatus of the present invention before all wire is removed from either spool. Inasmuch as each is identical, only one is described and Figures 6 and 13 illustrate the same as applied to the takeup spool. As shown, this means consists of a wirelike actuator I42 with a loop I43 therein. Loop I43 is adapted to enter groove I44 provided therefor in spool hub I35. By starting the winding of the wire 10 at a point indicated by arrow I45 in Figure 13, it will be observed that as the wire advances to the right of the hub the same will force loop I43 into groove I44.

As wire is removed from this spool, loop I43 is freed and due to centrifugal force moves outwardly. This allows the straight portion of the actuator, which is slidably positioned within the groove block I46 secured to the outer face of web I38, to move outwardly through an opening in the flange on such web. This outward movement of the actuator continues until arrested by the folded back end of the actuator contacting the lower surface of block I40.

In such outward position, actuator I42 contacts lever I41 fixed to the outer end of shaft I43. Such shaft I48 is journaled for rotation in a bearing provided in the previously mentioned bracket 21. To this shaft I48, the latch platev supporting lever 9| is fixed, and obviously, rota; tion of shaft I48 will effect shifting of latch plate 81.

Normally, lever I41 is in erect position. However, upon being contacted by actuatorv I 42', the

same is caused to oscillate. When wire is being unwound from the take-up spool, the same ro- 11 knob to return to off position before all wire is unwound off the spool, as loop I43 is freed before the unwinding wire reaches point I45 on hub I35.

In like manner, the actuator (not shown) provided on the wire spool moves outwardly, upon unwinding of such spool (clockwise), to contact a lever I49. As illustrated in Figure 7, lever I49 is fixed to the outer end of shaft I50 which is rotatably supported by bearing II provided by base I. At the other end of shaft I50, the latch plate supporting lever 90 is fixed, and rotation of shaft I50 will effect shifting of latch plate 81.

Lever I49 is, like lever I41, normally erect. However, upon being contacted by the actuator cammed by wire spool 3, such lever is caused to oscillate. Such oscillation serves to cause shifting of latch plate 81 for releasing pin 91 therefrom and permitting return of the control knob to off position.

The mechanism for applying a retarding force on cup I4 on the spool side of clutch I4I6 which drives spindle 6 and takeup spool 4 and the mechanism for delaying the driving of the capstan roller 56 and thus the feeding of wire until the control means is fully in play position, including the mounting of the capstan roller 56 and capstan drive roller 49 on a pivoted arm as distinguished from a fixed mounting of the rollers, form no part of the present invention but are disclosed and claimed in the copending application of DeVere C. Hollenbeck for Magnetic wire sound recording and reproducing apparatus, Serial No. 681,177, filed concurrently with this application.

It will be clear from the foregoing description that the apparatus shown in the drawings and described above has been illustrated and described in rather specific detail. Obviously, many modifications, changes and departures from the above described construction may be made without departing from the generic spirit and scope of the invention as set forth in the subjoined claims.

What is claimed is:

1. In a magnetic wire sound recording and reproducing mechanism, a wire feeding roller for feeding the wire at substantially uniform rate in one direction, a pivotally mounted pinch roller arm, a pinch roller mounted adjacent the outer end of said arm and adapted to press said wire into engagement with the feeding roller, pinch roller pressure applying means comprising a movable means for exerting constant pressure on the pinch roller arm and adapted to be moved outwardly thereon, and manually operated means for successively swinging the pinch roller arm into operative position and thereafter moving said pinch roller pressure applying means outwardly on said pinch roller arm.

2. In a magnetic wire sound recording and reproducing mechanism, a motor, a motor operated wire feeding roller for feeding the wire at substantially uniform rate in one direction, a pivotally mounted pinch roller arm, a pinch roller mounted adjacent the outer end of said arm and adapted to press said wire into engagement with the feeding roller, pinch roller pressure applying means comprising a spring loaded arm on said pinch roller arm and adapted to be moved outwardly thereon and said spring remain constant length throughout said movement, and control means for successively swinging the pinch roller arm into operative position and thereafter moving said spring loaded arm outwardly on said arm.

3. In a magnetic wire sound recording, and reproducing mechanism, a motor, a sound reproducing and recording head, a motor operated wire feeding roll for feeding the wire at substantially uniform rate in one direction, a pivotally mounted pinch roller arm'and a second pivotally mounted arm, a pinch roller mounted adjacent the outer end of the pinch roller arm and adapted to press the wire into engagement with the feeding roller, a second roller mounted adjacent the outer end of the secondly mentioned pivotally mounted arm and adapted tov bring the wire into said head, pinch roller pressure multiplying means comprising a movable means for exerting constant pressure on the pinch roller arm and adapted to be moved outwardly thereon, and manually operated control means for successively swinging the pinch roller arm into operative position and thereafter moving said pinch roller pressure applying means outwardly on said pinch roller arm and swinging the secondly mentioned arm into operative position.

4. In a magnetic wire sound recording and reproducing mechanism, a base, a motor on said base, a sound reproducing and recording head on said base, means on said base to support wire spools to be selectively driven by said motor, rotatable control means associated therewith to effect winding of the wire from either spool to the other, a motor driven wire feeding roller mounted on saidbase between said spools for feeding the wire at substantially uniform rate toward one spool, a pinch roller arm and a second arm pivotally mounted on said base and each adapted to be moved into operative position by said control means, a pinch roller mounted adjacent the outer end of the pinch roller arm and adapted to press the wire into engagement with the feeding roller, a second roller mounted adjacent the outer end of the secondly mentioned arm and adapted to bring the wire into said head, pinch roller pressure applying means comprising a member movable along the length of said arm and a spring for causing said member to exert a constant pressure on the pinch roller arm, means actuated by said control means for moving said member outwardly on said arm to increase the pressure exerted by the pinch roller without affecting the effort required to operate said control means.

IRVING A. STONE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Kuhlik Sept. 24, 1 46 

